Results 1 to 10 of about 253 (51)
Compact perturbations of operators with property (t)
Open Mathematics, 2021 Let ℋ{\mathcal{ {\mathcal H} }} be an infinite dimensional complex Hilbert space and ℬ(ℋ){\mathcal{ {\mathcal B} }}\left({\mathcal{ {\mathcal H} }}) the algebra of all bounded linear operators on ℋ{\mathcal{ {\mathcal H} }}.
Yu Xinling, Shi Weijuan, Ji Guoxing
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On hyponormality on a weighted annulus
Open Mathematics, 2021 In this work, we consider the hyponormality of Toeplitz operators on the Bergman space of the annulus with a logarithmic weight. We give necessary conditions when the symbol is of the form φ+ψ¯\varphi +\overline{\psi }, where φ\varphi and ψ\psi are ...
Sadraoui Houcine +2 more
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Remarks on hyponormal Toeplitz operators with nonharmonic symbols
Open Mathematics, 2023 In this article, we present some necessary or sufficient conditions for the hyponormality of Toeplitz operator Tφ{T}_{\varphi } on the Bergman space A2(D){A}^{2}\left({\mathbb{D}}).
Kim Sumin, Lee Jongrak
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Range-Kernel orthogonality and elementary operators on certain Banach spaces
Demonstratio Mathematica, 2021 The characterization of the points in Cp:1 ...
Bachir Ahmed +3 more
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Range-kernel weak orthogonality of some elementary operators
Open Mathematics, 2021 We study the range-kernel weak orthogonality of certain elementary operators induced by non-normal operators, with respect to usual operator norm and the Von Newmann-Schatten pp-norm (1 ...
Bachir Ahmed +2 more
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Concrete Operators, 2022 Let (X, 𝒜, μ) be a σ−finite measure space. A transformation ϕ : X → X is non-singular if μ ∘ ϕ−1 is absolutely continuous with respect with μ. For this non-singular transformation, the composition operator Cϕ: 𝒟(Cϕ) → L2(μ) is defined by Cϕf = f ∘ ϕ, f ∈
Zhou Hang
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Berezin number inequalities for operators
Concrete Operators, 2019 The Berezin transform à of an operator A, acting on the reproducing kernel Hilbert space ℋ = ℋ (Ω) over some (non-empty) set Ω, is defined by Ã(λ) = 〉Aǩ λ, ǩ λ〈 (λ ∈ Ω), where k⌢λ=kλ‖kλ‖${\mathord{\buildrel{\lower3pt\hbox{$\scriptscriptstyle\frown ...
Bakherad Mojtaba, Garayev Mubariz T.
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Product and factorization of hypo-EP operators
Special Matrices, 2018 In this article, we derive some necessary and sufficient conditions for the product of hypo-EP operators to be hypo-EP and we characterize hypo-EP operators through factorizations.
Johnson P. Sam, Vinoth A.
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Moments from their very truncations
, 2007 It is known that positive definiteness is not enough for the multidimensional moment problem to be solved. We would like throw in to the garden of existing in this matter so far results one more, a result which takes into considerations the utmost ...
Szafraniec, F. H.
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Berger measure for some transformations of subnormal weighted shifts
, 2014 A subnormal weighted shift may be transformed to another shift in various ways, such as taking the p-th power of each weight or forming the Aluthge transform.
Curto, Raul E., Exner, George R.
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